In vitro permeability studies of peritoneal (P), cuprophan (C), and polycarbonate (PCM) membranes.

: A unique dialysis device was developed to allow direct comparison of permeability characteristics of different membranes to various solutes under identical conditions. Studies with Cuprophan (CM), polycaronate (PCM), and peritoneal membrane (P) yielded the following results: 1. PCM is similar to CM in permeability to low molecular weight solutes. 2. PCM is significantly more permeable to middle molecular weight substances than CM or P. 3. P is more permeable to middle molecules than CM.